Cam released clutch



I l'z1/e r1l ar1 Lloyd flifor r] L J WOLF CAM RELEASED CLUTCH Filed June 12, 1948 July 24, 1951 Patented July 24, 1951 UNITED STATE PATENT OFFICE 2,561,833 CAM RELEASED GLUTCH L o d J. W f, Bee in Wis, ass gn r to w n Disc Clu ch Company, acine, Wis, a rp raion f W scons n Application June 12, 1948, Serial No. 32,664 5 Elaine. 1. roe--68) My invention relates olutehes anois con 'ned more particular y w h a de ign er or which is characteri ed by low manufacturing st eas of assembly, an the e m n tion of parts rdi ari onsider d ue sse y for eff ent operation.

ee object of the invention is t prov de. a clutch which is re l u elastic membe sueh. as a ub er ring. ha ur u i rm press r h ou hout the fri ion surfaces of the clutch.

A further ohieot is to dev a c utch o the character indicated wh c the e se mechanism mosses. cluteh rin ers a are rrang d for a mating o1: wan ering a t onl distinuished from a i ed ni nd wh ch are snarled to Sure their be n held e relea Pos o by the expanding pressur of th ading; r ng.

A furthero oieet is to pr ide a res li ntly a ledelutoh, n wh ch he finge s formi g p r or the release m ehani addit onal y interlook h theaotua ins eolla to prevent r la i e ro t ou t e eoiano also ct as ops to imi releasing m veme t. o t e l ar A further obj s a re uc ion in manufacturing oostthrough die casting certain members of the u h which i olucie hefrieti n sur ac s an chromium plat n some o the e m mbers 13 2! durab l ty and protecti n o the ass iated part against heat created (1 ng operation.

These, and. iurther oloi e s of he invention wil be set forth th fo lowin p o fie on, refnce being had to. he aoeompanyins, d awing, and the nov l means or whi h s d obje ts ar effeetuatezi will heoefiuitely pointed out n the claims.

In the drawing.

ssl and 2 are seet ona ele at ns o th lut h n n a d and; rel ased; posi ions soeetively.

3 is an end View of the clutch. lo kin he ciirectionor the arrow 3. in Fig,

Referring to the drawing, the numeral ll}, designates a hula-which is internally lgeyeglqr sp pad for engagement with a shaft (not shown that may be a driving or a driven member QWhlgh includes integral, annula flange that, serves asthe back or abutment plate ll of" the clutch. A Vabelt pulley ii is freely journaleq or; thehub portion it in juxtaposition to, plate ll acts as a driving or a driven member.

The opposite radial surface of the. eul ey- 2 constitute friction surfaces. of the dutch which coast, respectively, with the, adjacent ace ej therplate brand One side of: a pressure plate l4 which is internally toothed as at l5 in a plurality of lo ations fo r ta ing ngagement with a 11 rality o lon i ud nal y disp sed keyw ys 6, providecl in the periphery of the hub It}, the left end of each lze way ex nding from the rig t end of the hub to just beyond the pressure plate [5 in a axial pos t o s of the latt but terminat ng short of the left and of the hub. Three Such key- Way are illustrated in Fig. 3, but he numb may e va ied a desi ed- It. wil derstood that the pulley 12 may be replaced by other membe s for tr sm i power to or fr m th limb, to, such as for e mple, a plate which is per phera ly to thed for driving or driv n o gagem t w th internally toothed rin n acoor-clanee with tandard clutch practice.

The loading pressure for the clutch is supplied by rubber ring I T which is compressed between is. r cessed in the pe ip e of t e hub n, T

backin pla e therefore p ov d s a fixed bas f the extend a on of he rubber ring H whic in the dr vin p i ion of the clut h par ppli uniform annular pressure against the pressure plate lie that n turn rips the pulley I2 a a n t the. abutment plate H.

To release the clutch, the following instrumentalities are emeloyed- An longat d; r leas fingel; 23 is mounted, for relatively free rocking mo m nt ineachof he keyw ysj l6 and the left end-of each finger includes a radially outward nose 2! whi h at a time is positioned betw n the, associated pressure plate tooth l5 and the end all 2:2 of th kcyuay It. The spacing of this tooth a d Wa l s wa less than the width of the ose 2.! so thatthe latter does not, hinder the movement of the pre svr olate I4 to driv n posi ou and t e no e and of the finger 20 may be o ked in h eywar 6 du g r lease ofthe 2 11 4011- Th i ht end orthe fi ger 211 includes. a portion which an le outwardly of th eyway Hi a d awayi o the backing lat 8 inth positi n of pa show in F gl, T e outer profile of the linger portion. 23 i egular and is defined by a inter-m diate cam Surface 24 and inner and oute am. surf ces 5 and 2 respectiv ly- Th ur eee at isl s n l ne with respect. to the axis of the clutch than are the surfaces Ziand 26 ier err r-pose. present yspla neu and in the drivng oo itio of the eluteh as s own in F gla the surieee 2 is re ei edlwthin a slotll out partialwith the associated keyway It. The base of the I tained in the position shown by centrifugal force and if power flow should be interrupted and the clutch ceases rotation in the engaged position,

aluminum base, or any alloy which is commonly used for die casting. This method eliminates considerable machining since the indicated parts may be cast to close tolerances. For durability and to secure the effect of dissimilar surfaces between the pulley and the hub, the outer surfaces of the hub, including the abutment plate ll and the keyways l6, have applied thereto a hard plating of chromium.

I claim: v

1. In a clutch, the combination of a hub having an annular flange constituting a friction element, a friction member journaled on the hub in coacting relation to the element, an annular, pressure plate connected to the hub and shiftable to frictionally grip the member against the element; an annular, backing plate on the hub any finger that may be in a position to be gravity dropped radially inward of its associated keyway is prevented from moving sufficently to entirely disengage from the slot Z'f by the nose 2! contacting the pressure plate l5.

, The clutch is disengaged by moving the shifting collar 28 towards the right to the position illustrated in Fig. 2. During this movement, the bases of the collar slots 21 ride along the cam surfaces 25, rocking the clutch fingers inwardly of the keyways I6 and causing the noses 2| to bear against the pressure plate teeth I5. The fulcrum for eachfinger during this movement is provided by the wall 22 against which bears the left extremity of the finger radially inward of the nose. 2|, denoted by the numeral 29, and the result of the movement, as shown in Fig. 2, is to move the pressure plate [4 towards the right, further compressing the rubber ring I! and freeing the friction surfaces of the pressure theretofore exerted by the latter ring.

The releasing movement of the collar 28 is limited by engagement of the bases of the slots 21 with the cam surfaces 26 which act as stops and, in this position of parts, the intermediate surfaces 24 are substantially parallel to and bear against those parts of the inner, annular surface of the collar28 which register with the keyways l6, these'parts being denoted by the numeral 30. Hence, the extending force of the rubber ring ll in the release position is transmitted through the olutchfingers 20 and radially outward against the collar surface 30 through the finger surfaces 24, these surfaces being substantially parallel to the clutch axis and thus maintaining the collar 28 in the release position and obviating any eX- traneous factors for accomplishing this result.

An important advantage of the above construction is the fact that the fingers 20 not only perform their primary function as releasing agents, but also serve as keys for preventing rotation of the collar 28 relative to the hub l0 and as stops for this collar, thereby eliminating the necessity for additional keys and stop elements for these purposes. These design features are. refiected in obvious manufacturing advantages in that they materially reduce costs.

The clutch is compact, simple in construction, and is easy to assemble since the parts may be mounted on the hub in an obvious manner and the rubber ring I! is then compressed sufficiently to permit the snap ring 19 to be seated in position, thus establishing suflicient initial compressionin the ring I! to effect the desired engagement of the friction surfaces.

As a further means of reducing costs, the hub Ill, including its integral abutment plate H, and the pulley 12 are diecast out of a suitable material, which may be those having a'zinc or an spaced and held against axial movement away from the pressure plate, a rubber ring compressed on the hub, and release fingers actuated by the between the plates and acting to shift the pressure plate to gripping position, a collar slidable collar and engageable with the pressure plate for further compressing the rubber ring and releasing the member, the fingers being positioned around the hub within the collar and one end of each finger extending through the pressure plate to engage the gripping side thereof.

, 2. In a clutch, the combination of a hub having longitudinal keyways spaced around and opening radially outward thereof and an annular friction member, a second friction member journaled on the hub in coacting relation to the annular member, an annular, pressure plate having teeth fitting into the keyways and shiftable to frictionally grip the members, an annular backing plate on the hub spaced and held against axial movement away from the pressure plate, a rubber ring compressed between the plates and acting to shift the pressure plate to gripping position, and means for releasing the members comprising a release finger rockable in each keyway and having one end engageable with the adjacent pressure plate tooth in a direction to further compress the resilient means, and a collar shiftable on the hub and engageable with cam surfaces on the'opposite ends of the fingers to rock the same, the fingers fulcruming against the keyways during the releasing movement. r

3. In a clutch, the combination of a hub having longitudinal keyways spaced around and opening radially outward thereof and an annular friction member, a second friction member journaled on the hub in coacting relation to the annular member, an annular, pressure" plate having teeth fitting into the keyways and shiftable to frictionally grip the members, an annular, backing plate on the hub spaced and held against axial movement away from the pressure plate, a rubber ring compressed between the plates and acting to shift the pressure plate to gripping position, and means for releasing the members 7 comprising a release finger rockable in each keylar friction member, a second friction member journaled on the hub in coacting relation to the annular member, an annular, pressure plate having teeth fitting into the keyways and shit-table to frictionally grip the members, an annular, backing plate on the hub spaced and held against axial movement away from the pressure plate, a rubber ring compressed between the plates and acting to shift the pressure plate to gripping position, means for releasing the members comprising a release finger rockable in each keyway and having one end engageable with the adjacent pressure plate tooth in a direction to further compress the resilient means and a cam surface at the opposite end and a collar shiftable on the hub and engageable with the cam surfaces to rock the fingers, the fingers fulcruming against the keyways during the releasing movement, and a stop provided on each finger for limiting the releasing movement of the collar.

5. In a clutch, the combination of a hub having longitudinal keyways spaced around and opening radially outward thereof and an annular friction member, a second friction member journaled on the hub in coacting relation to the annular member, an annular, pressure plate hav-- ing teeth fitting into the keyways and shiftable to frictionally grip the members, an annular, backing plate on the hub spaced and held against axial movement away from the pressure plate, a rubber ring compressed between the plates and acting to shift the pressure plate to gripping position, means for releasing the members comprising a release finger rockable in each keyway 5 and having one end engageable with the adjacent pressure plate tooth in a direction to further compress the resilient means and a cam surface at the opposite end and a collar shiftable on the hub and engageable with the cam surfaces to rock the fingers, the fingers fulcruming against the keyways during the releasing movement, and other surfaces on the collar and fingers arranged to coact when the collar is in fully released position, said last named surfaces being disposed substantially parallel to the clutch axis whereby the extending action of the resilient means maintains the collar in release position.

LLOYD J. WOLF.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 890,810 Stacks June 16, 1908 1,407,384 Crowley Feb. 21, 1922 1,450,202 Crowley Apr. 3, 1923 1,985,422 Pearmain Dec. 25, 1934 2,070,065 Pearmain Feb. 9, 1937 2,174,240 Glenney Sept. 26, 1939 2,287,608 French June 23, 1942 2,367,390 Firth et a1 Jan. 16, 1945 FOREIGN PATENTS Number Country Date 134,695 Germany Sept. 30, 1902 

